Collapsible stools and chairs



June 9, 1964 A. SPRIGMAN 3,136,272

COLLAPSIBLE STOOLS AND CHAIRS Filed March 15, 1962 3 Sheets-Sheet 1 2/ Z7 INVENTOR. ART/IMF 5Fk/6MA V June 9, 1964 A. SPRIGMAN COLLAPSIBLESTOOLS AND CHAIRS 3 Sheets-Sheet 2 Filed March 15, 1962 June 9, 1964 A.SPRIGMAN 3,136,272

COLLAPSIBLE STOOLS AND CHAIRS Filed March 15, 1962 3 Sheets-Sheet 3XX/MMM,

United States Patent 3,136,272 C(DLLAPSIBLE STGGLS AND CHAIRS ArthurSprigman, New Hyde Park, N.Y., assignor to Murray Lifl', Brooklyn, NY.Filed Mar. 15, 1962, Ser. No. 179,911 3 Claims. (Cl. 108-118) Thisinvention relates to collapsible stools and chairs. It is the principalobject of the present invention to provide collapsible stools or chairsto which the flexible seat portion will be so connected to theoutwardly-extending upper ends of the chair legs that it will not beunduly strained, the load being assumed by flexible strap loopsextending under and along the four sides of the seat portion at an angleto one another and connected to the upper ends of the chair legs byspecially prepared block means for receiving the loops.

It is another object of the invention to provide a collapsible stool orchair which will have crossed legs on four sides of the chair, and inwhich the upper and lower ends of the cross leg members are joined byupper and lower specially prepared blocks from which the seat portionand the foot projection will respectively extend.

It is still another object of the invention to provide a collapsiblestool or chair having the above objects in mind, which may have arm andback rests and carried by vertically-extending posts extending throughupper and lower blocks on collapsible crossed leg members and collapsingtherewith.

It is a further object of the invention to provide a collapsible stoolor chair having the one immediately above object in mind, in whichfastener catches are unnecessary to lock the seat portion to the posts,the outward extension of the crossed leg members being limitedautomatically by the nature of the construction, in which there arepairs of crossed legs lying on all four sides of the chair and joinedtogether at the corners by blocks disposed at their upper and lowerends.

Other objects of the invention are to provide collapsible and portablestools or chairs having all of the above objects in mind, which will beof simple construction, inexpensive to manufacture, has a minimum numberof parts, light in weight, durable, wherein the parts are paralleledwith one another when collapsed and making for a compact item forstorage in an auto trunk or other limited storage spaces, easy to openand collapse, free of sliding parts, comfortable, of pleasingappearance, and effective and efficient in use.

A still further object of the inventionis to provide a collapsible chairstructure having the foregoing objects in mind and in addition havingconvenient means to lock the structure in its open position.

For other objects and for a better understanding of the invention,reference may be had to the following detailed description taken inconnection with the accompanying drawing, in which- FIGURE 1 is aperspective view of the opened collapsible stool or chair constructedaccording to one form of the invention,

FIG. 2 is an enlarged fragmentary perspective view of the upper end ofthe collapsed stool,

FIG. 3 is a fragmentary top plan view of one corner of the opened top ofthe stool with the corner of the flexi ble seat material lifted to showone of the corner blocks,

FIG. 4 is a fragmentary side elevational view of a corner of the openedstool,

FIG. 5 is a transverse sectional View of thecorner block as viewed online 5-5 of FIG. 4.

FIG. 6 is a transverse sectional view taken through the intersection ofthe crossed leg members as viewedon line 6-6 of FIG. 2,

FIG. 7 is a fragmentary top plan view of the foot bloc V ner in whichone of the legs is spread from the foot block upon the stool beingopened,

FIG. 9 is a perspective View of'an opened collapsible chair constructedaccording to a modified form of the invention with a back thereon andemploying corner blocks for supporting the chair seat and cross legbraces, FIG. 10 is a fragmentary plan view of one corner of the seat ofthe opened chair, FIG. 11 is a fragmentary side elevational view cornerof the seat part of the chair, 7

FIG.- 12 is a fragmentary transverse sectional view of the one corner ofthe chair asviewed on line 12-12 of FIG. 11,

of one FIG. 13 is a fragmentary transverse sectional view of the chairtaken through one side of the back part thereof as viewed on line 13-13of FIG. 9,

FIG. 14 is a fragmentary transverse sectionalview looking in plan uponthe crossed brace bracket at the lower end of one chair leg and asviewed on line 14-14 of FIG. 9,

FIG. 15 is a fragmentary elevational view of the top part of thecollapsed chair,

,FIG. 16 is a perspective view of an alternative chair form of theinvention in which a twist lock mechanism has been provided to preventthe collapsing of the chair until so desired,

FIG. 17 is a fragmentary plan view through 17-17 of FIG. 16 to show theseat strap securing fittings,

FIG. 18 is a fragmentary view in side elevation through 18-18 of FIG. 16showing the twist lock member in its unlocked position, FIG. 19 is aplan view taken on line 19-19 of FIG. 18, FIG. 20 is a sectional viewtaken on line 20-20 of FIG. 19,

FIG. 21 is a view taken on line 21-21 of FIG. 17,

FIG. 22 is a view taken on line 22-22 of FIG. 16,

FIG. 23 is a view taken on line 23-23 of FIG. 18, and

' FIG. 24 is a plan view. taken on line 24-24 of FIG. 16. Referring nowparticularly to FIGS. 1 to 8, 21 repre sents corner blocks, there beingfour in' number, on the stool or chair to which crossed leg members orbraces 22 and 23 of pairs of crossed leg members located respectively onfour sides of the chair, are respectively pivotally connected, angledninety degrees from each other and connected to the corner block andwithin respective bifurcations 24 and 25 thereof by respective pivotpins 26 and 27 as best shown in FIG. 5 and with the ends of the legmembers respectively having tongue projections 28 and 29 to fit therespective bifurcations 24 and 25, FIG. 5. Each pair of the crossed legmembers --22 and 23, there being four pairs in number, one on each sideof the stool, and pivotally joined with one another by a pivot pin 31extend through the leg members as best viewed in FIGS. 2 and 6, andupset in rivet fashion as indicated at 32 and 33, to hold the legmembers together. A spacing washer 34 is provided between the cross legmem bers to keep'them spaced from one another and from binding whenbeing collapsed or opened, The lower ends of crossed legs 22, 23 of therespective pairs are joined in a similar manner to foot blocks 36 havingrubber cushions 37 on their bottom faces for engagement with the flooror ground surface in a non-skid manner and fixed thereto by rivet 38.

j The lower ends of the leg members 22, 23 respectively have tongueportions 39, 41 that are respectively pivotal- Patented'June 9, 1964 saners 1y secured to bifurcated portions 42 and 43, extending ninetydegrees from one another, by respective pivot pins 44, 45. Thus, it willbe .seen that the upper and lower ends of the cross leg members 22 and23 are adapted tovbe collapsed upon one another about their pivot pin 31while being retained at their upper and lower ends by the seat and footblocks 21 and 36.

The seat blocks 21 are extended in height and are fashioned to receivein a manner, similar to which it receives the upper ends of the crossleg members 22 and 23, strap loops 46 and 47 running across the sides ofthe flexible seat portion 48 to the underside of which they are stitchedas indicated at 49. These strap loops receive all of the strain of theweight of a person seated onthe stool. The upper portion of the block 21is cut to provide recesses 51 and 52, ninety degrees apart and intowhich respective strap loops 46 and 47 extend and are retained byrespective pins 53 and 54 running through the recesses and therespective loops 46 and 47. The corner of the seat portion as best seenat 55 is not put under strain and overlies the block 21 to cover thesame. Thus, with the flexible and foldable seat portion 48 so connectedwith the stool leg members so as not to be put directly under strain, itwillstand up longer and enhance the life of the stool.

' When the stool or chair is opened as shown in FIG. 1 and weight isapplied to the seat, the outward extent of the upper ends of the legmembers and their distance from one another and connection with loopsare such that the weight is so distributed that there is a tendency toforce their outer ends and the blocks 21 outwardly and downwardly andovercenter rather than inwardly and upwardly. When the stool is relievedof its weight on its seat portion and with the seat material beingflexible, the upper ends of the leg members and the blocks 21 are drawntoward one another from what may be considered an overcenter positionand readily and easily the leg members are folded and collapsed uponthemselves so that the stool consumes little space for the purpose ofbeing stored. In thisform of the invention, there has degrees from eachother into which the respective strap loops 67 and 68 of the flexibleseat portion 66 are respectively secured by their respective pins 81 and82. These strap loops 67 and 63 are secured to the seat portion 66respectively by stitchings 33 and extend across the full side of theseat 66 so that the strain on the seat bottom resulting from the weightof the person sitting therein is assumed by the loop straps. The cornersof the seat portion 66 are cut away at 84 since they need to assume noneof the seat strain and to accommodate the corner posts 61. The arm rests64 have loops 85 on their front and rear ends and are joined to theupper ends of the posts by metal rings 86.

The rear posts 61 are respectively provided at their upper ends withblocks 67 that are fixed thereto by pins 88 and for the purpose ofsupporting the back rest 65. Journalled in these respective blocks 87are pins 89 that respectively extend laterally from vertically-extendingrods -91 about which loop seams 92 of the back rest 65 are extended andsupported. This back rest can thus swivel on the blocks 87 toaccommodate the inclination of the back of the person and can fold upalong with the arm rests 64 being of flexible material and .along withthe folding of the brace rods 57 and 58, the seat portion 66 and thebringing'together of the posts, 61, all in the manner as best shown inFIG. 15 with the parts collapsed and folded upon one another.

It will be seen that there has also been provided a foldable chair inwhich only the blocks 59 slide upon vertical posts 61 and in which thereis no need for fixing the blocks 59 to the post 61 when the chair partsare extended. The cross legs in their'connections with the post 61measure the distance to which the chair parts been a complete absence ofvertically-extending posts and/or friction-binding sliding parts. Theoutward ex tension of the parts and the height of the stool is readilylimited by the joining together of the lower'ends of the legs by thefoot blocks 36 and of the strap loops 46 and 47 with the upper blocks21.

Referring now to FIGS. 9 to 15, there is shown a collapsible chairconstructed according to another form of the invention in which crossbraces 57 and 58 of four pairs of cross braces are joined to cornerblocks 59 at their upper ends that are respectively slidable uponrespective vertically-extending posts 61 while their lower ends arejoined to bottom blocks 62 which do not serve' as foot members but whichare fixed by pins 63' to the lower ends of the post 61. There are fourpairs of crossed braces 57' and 58 and four posts 61 that serve as footmembers, carry arm rest straps 64 at the opposite sides of the chair anda back rest 65. The provision of the blocks 59,- 62 and the connectionof the cross braces 57 and 58 therewith is the same as with the firstform of the inventionp Likewise, a seat bottom portion 66 is similarlyconnected by strap loops 67 and 68 to the corner blocks 59 by respectivepins 81 and 82. The only real difference in the construction of thissecond form of the invention is thus the inclusion of the posts perblocks 59 have bifurcated portions 71 and 72 that respectively receiverespective tongue portions 73 and 74 of respective cross members 57 and58 and respectively secured thereto by pivot pins 75 and 76.

' Each block 59 has recesses 78 and 79 angled ninety are extended andthe weight of the person on the seat portion 66 will force the blocks 59downwardly on the post 61 and the upper ends of the braces intoovercenter positions.

To collapse the chair the blocks 50 are drawn upwardly on the posttoward the rings 86 and the back rest blocks 87 so that all the parts ofthe chair are substantially paralleled with one another as best shown inFIG. 15. Referring now to FIGS. 16 through 24, 'four pairs ofleg'meinbers 161 and 102 are each pivoted on pins 103 to form fourcompressioned support trusses. Each member 101 and 102 is pivotallysecured at its lower end to a foot block 164, and at its upper end to aseat block 106. Four corner posts 107 are secured at their lower ends toblocks 10? while slideably passing freely through blocks 1'36. Each seatblock 166 has secured to it two straps 108 and 169 at right angles toone another by means ofthe hangar members 111, straps 108 and 109 aresecured to a flexible seat member 112 by means of stitching 113.

A flexible back rest member 114 is pivotally secured to the rear cornerposts 167 by the spreader members 116 and pivot blocks 116. Arm rests117 are secured to corner posts 107 by hangar members 118.

Thus far the chair of FIG. 16 is substantially identical with that ofFIG. 9. However, the two side truss pairs 101, 102, are each providedwith a folding locking strut assembly comprising hinge studs 119, 121,hinge pin 120, struts 122, 123, and pivot pins 127 and 128. Strut 122 ispivotally secured to legmernber 101 by pin 127 while strut 123 issimilarly pivoted to leg 102 by pin 128.

The two hinge studs 119, 121 are journalled and secured together byhinge pin 120. a A cylindrical stud portion of hinge stud 119 fitswithin and is journalled in the hollow tubular body of strut 122, whilea corresponding cylindrical portion of hinge stud 121 fits within and isjournalled in the hollow tubular body of strut 123. An annular groove129 in stud 112 cooperates with a pin 131 in strut 122 to retain stud119 on strut 122 while allowing angular rotation therebetween. In likemanner, annular groove 132 in hinge stud 121 cooperates with pin 133 intubular strut 123 to retain them together while allowing co-axialangular rotation therebetween. It can be seen that the hinge assembly119, 120, 121 can be rotated only when struts 122 and 123 are foldedabout pins 127 and 128 so as to'be co-axial as in FIGS. 16, 19, 20 andthe solid line position illustrated in FIG. 18.

In the unlocked position of hinge pin 120 shown in FIG. 18, pin 120 hasits axis parallel to the axes of pins 127 and 128. Consequently, struts122 and 123 can be angulated into the dotted position shown in FIG. 18thereby permitting the chair to be folded into its closed position.

Conversely, after the chair is opened to the position corresponding tothe solid lines of FIG. 18, the hinge members 119 and 121 on each side,together with hinge pins 120 may be rotated ninety degrees to theposition shown in FIG. 20. By virtue of the fact that the axis of pin120 is now rotated ninety degrees away from the axes of pins 127 and128, struts 122 and 123 are now incapable of displacement into the openposition, and the chair structure is locked in its open position.

This condition will persist until pins 120 are again rotated into theunlocked position shown in FIG. 18.

While various changes may be made in the detailed construction, it shallbe understood that such changes shall be within the spirit and scope ofthe present invention as defined by the appended claims.

What is claimed is:

1. A collapsible self-locking chair comprising pairs of crossed bracelegs pivoted to one another intermediate the length thereof, upperblocks pivotally receiving the upper ends of adjacent four pairs ofcrossed legs arranged ninety degrees apart from one another andrespectively along the front, rear and sides of the chair, a seatportion having straps running to the corners of the seat portion at anangle to one another and means for respectively joining said seat strapsto the block at a corresponding angle with the respective pairs of crosslegs, the extremities of the straps being spaced such a distance apartas to allow outward overcentering downward force upon the blocks tendingthereby to spread the crossed legs and seat portion to its open positionwhen the seat portion is weighted, whereby the seat portion proper willbe relieved from the seat strain and the straps will apply over centerdownward force upon the blocks when the chair is opened, each of saidupper blocks having bifurcated portions angled ninety degrees from oneanother, saidcrossed legs having tongue portions extending into thebifurcated portions of the blocks and pivot pins extending through thebifurcated and tongue portions to pivotally join the crossed legs to theblocks, and said upper blocks having recesses correspondingly cuttherein above the bifurcated portions and similarly angled ninetydegrees apart and said straps being in forms of loops extending into therespective recesses and pins carried on the upper block and extendingthrough the recesses and the loops to secure the loops to the blocks.

2. A collapsible self-locking chair comprising pairs of crossed bracelegs pivoted to one another intermediate the length thereof, upperblocks pivotally receiving the upper ends of adjacent four pairs ofcrossed legs arranged ninety degrees apart from one another andrespectively along the front, rear and sides of the chair, a seatportion having straps running to the corners of the seat portion at anangle to one another and means for respectiveley joining said seatstraps to the block at a corresponding angle with the respectivepairs ofcrossed legs, the extremities of the straps being spaced such a distanceapart as to allow outward overcentering downward force upon the blockstending thereby to spread the crossed legs and seat portion to its openpositionwhen the seatportion is weighted, whereby the seatportion properwill be relieved from the seat strain and the straps will apply overcenter downward force upon the blocks when the chair is opened, each ofsaid upper blocks having bifurcated portions angled ninety degrees fromone another, said crossed legs having tongue potrions extending into thebifurcated portions of the blocks and pivot pins extending through thebifurcated and tongue portions to pivotally join the crossed legs to theblocks, and said upper blocks having recesses correspondingly cuttherein above the bifurcated portions and similarly angled ninetydegrees apart and means for securing the ends of the straps in therecesses in the blocks.

3. The collapsible self-locking chair as defined in claim 1 andvertically extending posts slidably mounting said upper blocks andfixedly mounting the lower blocks, the pair of crossed legs at each sideof the chair having a folding locking strut assembly including opposedinterlocking hinge studs, a hinge pin extending through the opposedhinge studs, a tubular strut pivotally secured to one side leg and toone stud, and a tubular strut pivotally secured to the other side legand to the other stud, said studs having stop faces for engaging oneanother as the tubular struts are pivoted upon their pivot connectionwith the legs to thereby limit the folding movement of the struts whilepermitting the folding of the struts in a diametrically oppositedirection for the collapse of the legs, said hinge studs beingjournalled in the struts thereby permitting the studs to be turned inthe struts and whereby to lock the struts in their extended positionsand the legs to be braced against inward collapse.

References Cited in the file of this patent UNITED STATES PATENTS244,215 Fenby July 12, 1881 283,119 Knapp Aug. 14, 1883 398,943 CrandallMar. 5, 1889 1,185,568 Zeunert May 30, 1916 1,285,580 Bachtel Nov. 26,1918 1,381,136 Ribeiro June 14, 1921 1,390,836 Stoll Sept. 13, 19211,481,521 Marsh Jan. 22, 1924 1,509,881 Severin Sept. 30, 1924 1,842,338Wenz'et al. Jan. 19, 1932 1,942,112 McQuilkin Ian. 2, 1934 2,818,910Hawkins Jan. 7, 1958 FOREIGN PATENTS 666,871 Great Britain Feb. 20, 19521,112,257 France Nov. 9, 1955 856,035 Great Britain Dec. 14, 1960

1. A COLLAPSIBLE SELF-LOCKING CHAIR COMPRISING PAIRS OF CROSSED BRACELEGS PIVOTED TO ONE ANOTHER INTERMEDIATE THE LENGTH THEREOF, UPPERBLOCKS PIVOTALLY RECEIVING THE UPPER ENDS OF ADJACENT FOUR PAIRS OFCROSSED LEGS ARRANGED NINETY DEGREES APART FROM ONE ANOTHER ANDRESPECTIVELY ALONG THE FRONT, REAR AND SIDES OF THE CHAIR, A SEATPORTION HAVING STRAPS RUNNING TO THE CORNERS OF THE SEAT PORTION AT ANANGLE TO ONE ANOTHER AND MEANS FOR RESPECTIVELY JOINING SAID SEAT STRAPSTO THE BLOCK AT A CORRESPONDING ANGLE WITH THE RESPECTIVE PAIRS OF CROSSLEGS, THE EXTREMITIES OF THE STRAPS BEING SPACED SUCH A DISTANCE APARTAS TO ALLOW OUTWARD OVERCENTERING DOWNWARD FORCE UPON THE BLOCKS TENDINGTHEREBY TO SPREAD THE CROSSED LEGS AND SEAT PORTION TO ITS OPEN POSITIONWHEN THE SEAT PORTION IS WEIGHTED, WHEREBY THE SEAT PORTION PROPER WILLBE RELIEVED FROM THE SEAT STRAIN AND THE STRAPS WILL APPLY OVER CENTERDOWNWARD FORCE UPON THE BLOCKS WHEN THE CHAIR IS OPENED, EACH OF SAIDUPPER BLOCKS HAVING BIFURCATED PORTIONS ANGLED NINETY DEGREES FROM ONEANOTHER, SAID CROSSED LEGS HAVING TONGUE PORTIONS EXTENDING INTO THEBIFURCATED PORTIONS OF THE BLOCKS AND PIVOT PINS EXTENDING THROUGH THEBIFURCATED